Hello! I (tried, at least) converted an old laptop to a Debian home server, and I was trying to set up duckdns.org and to enable port forwarding on my router. internet connection was working, I installed packages, docker, immich, etc, and then suddenly (I don’t know exactly when) it refuses to connect to the internet. It does connect to local addresses (I can ssh into it) but ping google.com and any other internet-involving command fail. I had set up a rule on the router to forward port 80 to the device’s port 80, but I then removed the rule and it still does not connect to the internet. I rebooted the router but nothing changed. Any idea what could be? the router is a Vodafone router.

I changed the hostname to debianserver but on the router it is still written debian. Also, it’s the only device with unknown ipv6

thanks in advance!

  • Stantana@lemmy.sambands.net
    0·
    10 months ago

    I understand you might be a bit stressed out, but it’s very hard to make head or tails of what you’re describing.

    E.g. What do you mean by “no internet connection”? Does it mean just the old laptop, all devices on the network or the router itself?

    • tubbadu@lemmy.kde.socialOP
      0·
      10 months ago

      thanks for the answer! Sorry I didn’t specified very well: only the server has problems, all other devices work as before

      • Stantana@lemmy.sambands.net
        0·
        10 months ago

        I bet it has something to do with the LAN DHCP setup, since you have to set a static IP for the server…

        Update - That won’t work at all if it is indeed the issue. Let me think for a sec on how to pull external ip by doing a IP wget…

          • Stantana@lemmy.sambands.net
            0·
            10 months ago

            Yeah, I realized after the fact. This should work: wget 104.18.114.97, and you should get a ERROR 403: Forbidden if your server has any internet connection.

            • tubbadu@lemmy.kde.socialOP
              0·
              10 months ago
              tubbadu@debianserver:~$ wget 104.18.114.97
--2024-01-18 21:35:38--  http://104.18.114.97/
Connecting to 104.18.114.97:80... failed: No route to host.

              really really thanks for the help!

              • Stantana@lemmy.sambands.net
                0·
                10 months ago

                Please try wget https://104.18.114.97, if this one goes through I’d think the problem could be related to a faulty forwarding of regular internet traffic (port 80). If that fails as well I’d guess it’s to due with the DHCP/Static IP’s and involves your router. I’m absolutely clueless about Vodafone routers though.

                Edit: Any connection would show “The certificate’s owner does not match hostname ‘104.18.114.97’”

                • tubbadu@lemmy.kde.socialOP
                  0·
                  10 months ago

                  Edit: Any connection would show “The certificate’s owner does not match hostname ‘104.18.114.97’”

                  sorry I don’t think I understand, where should this be written?

  • Maestro@kbin.social
    0·
    10 months ago

    My guess is that you have Docker configured incorrectly. Its internal IP range probably overlaps with your real network, so all requests are routed to Docker. Uninstall docker and reboot the server. If that works, reinstall docker and properly configure its internal networking.

  • Petter1@lemm.ee
    0·
    10 months ago

    Is there a reset button somewhere on the router? Most of them have something like this in order to reset them to factory settings. If not, google for your device name and factory reset, maybe it’s something like „press button while turning on“ etc. I’d try something like that

    • tubbadu@lemmy.kde.socialOP
      0·
      10 months ago

      Yes there is in the web UI a factory reset button, but I’d rather not do this because it has some settings by other people

      • elucubra@kbin.social
        0·
        10 months ago

        So, several people share the router and can modify settings…
        That’s a recipe for trouble.

        I do external support for small businesses. When I work, configure etc. sometning, I change the password. I write the password on a piece of paper and put it in an envelope. Then I sign across the sealed flap. That envelope is handed to the customer. If I cease to work for them or something happens to me, they can open it and retrive the password. If something goes belly up, I ask for the envelope. If the envelope has been tampered, I wash my hands, and chrge handsomly to solve the issue.

        I’d reset it, and then make someone responsible for doing things to the router, that way everyone knows what’s going on.

  • mozz@mbin.grits.dev
    0·
    10 months ago

    Does ping 8.8.8.8 work? (To check if it’s DNS)

    What’s ip route show say? (Just to try to narrow down whether it’s an issue with the server’s config or the router’s)

    What’s traceroute 8.8.8.8 display?

    • tubbadu@lemmy.kde.socialOP
      0·
      10 months ago

      thanks for the answer!

      ping 8.8.8.8 fails, and I don’t have traceroute installed (and no internet to install it)

      tubbadu@debianserver:~$ ip route show
0.0.0.0 dev veth3492bf7 scope link
0.0.0.0 dev vethc1bf668 scope link
0.0.0.0 dev vethb41fd7e scope link
0.0.0.0 dev veth2e39932 scope link
0.0.0.0 dev veth68451d9 scope link
default dev veth3492bf7 scope link
default dev vethc1bf668 scope link
default dev vethb41fd7e scope link
default via 192.168.1.1 dev enp1s0
169.254.0.0/16 dev veth68451d9 proto kernel scope link src 169.254.210.75
169.254.0.0/16 dev veth2e39932 proto kernel scope link src 169.254.242.12
169.254.0.0/16 dev vethb41fd7e proto kernel scope link src 169.254.185.90
169.254.0.0/16 dev vethc1bf668 proto kernel scope link src 169.254.225.22
169.254.0.0/16 dev veth3492bf7 proto kernel scope link src 169.254.123.220
172.17.0.0/16 dev docker0 proto kernel scope link src 172.17.0.1 linkdown
172.18.0.0/16 dev br-56cf32fc7cde proto kernel scope link src 172.18.0.1
192.168.1.0/24 dev enp1s0 proto kernel scope link src 192.168.1.9
192.168.1.1 dev enp1s0 scope link
      • mozz@mbin.grits.dev
        0·
        10 months ago

        This is kind of a nutty network config. It looks like docker is setting up extra default routes, which I could easily see fouling everything up. As a first experiment (warning, this may ruin your networking until the next reboot):

        ip route flush 0/0
ip route add default via 192.168.1.1 dev enp1s0

        … and see if that makes things work (start with ping 192.168.1.1 and ping 8.8.8.8). If that solves the problem, then I think something about your docker config is adding stuff to your networking that’s causing the problem; maybe remove/disable docker completely and then re-add docker things one at a time to see where the problem comes in.

        • tubbadu@lemmy.kde.socialOP
          0·
          10 months ago

          okay, I thought to have solved the problem but I was wrong, here I go again. When I docker compose up -d the immich server (the only one I have installed) all those routes are created, and apparently some of them conflicts with something else and now my host has no internet connection. however it seems that ip route flush 0/0 solves the problem until the reboot, which is strange. the other command returns RTNETLINK answers: File exists

          • mozz@mbin.grits.dev
            0·
            10 months ago

            Hm. Yeah, that’s weird. The default routes you’re seeing should basically never exist, so it sounds like there’s some kind of manual network config happening inside the Docker container that’s creating a broken network.

            What does docker network inspect [network] say for each of your Docker networks (substituting each Docker network for “[network]”)? What’s the network section of docker-compose.yml look like?